U.S. Pat. No. 2,924,752 describes a shunt effect three-pole circuit breaker, which provides effective protection of cables and receivers downstream from the circuit breaker by creating a short-circuit internal to the circuit breaker when the latter opens. The short-circuit occurs on the three phases and the three pairs of contacts are subjected to the short-circuit current and are equipped with arc chutes. A circuit breaker of this kind is of limited value.
The present invention is based on the observation that the shunt effect protecting cables can be used in certain cases for protection of circuit breaker parts, which can then be simplified or designed to perform additional functions.